Saturated disulfides



United States Patent C) 3,141,045 SATURATED DISULFIDES Paul C. Ai'chenegg, Prairie Village, Kans., and Carl D.

Emerson, Kansas City, Mo., assignors to Chemagro Corporation, New York, N.Y., a corporation of New York No Drawing. Filed Dec. 6, 1961, Ser. No. 157,589 11 Claims. (Cl. 260-608) This application is a continuation-in-part of application Serial No. 143,013, filed September 28, 1961'.

The present invention relates to novel asymmetrical disulfides, methods of making the same and their use as pesticides.

It is an object of the present invention to prepare novel polyhaloethyl alkyl or aryl or haloaryl disulfidesv Another object is to prepare improved compositions and processes for killing nematodes.

A further object is to prepare improved compositions and processes for killing fungi.

An additional object is to prepare improved compositions and processes for killing bacteria.

Still further objects and the entire scope of applicability of the present invention will become apparent from the detailed description given hereinafter; it should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

It has now been found that these objects can be attained by preparing compounds having the formula where R is hydrocarbon or haloaryl, R is hydrogen or chloro or bromo, R and R are chloro or bromo and R is hydrogen, chloro or bromo'. At least 3 of R R R and R are halo.

It will be observed that all of these compounds have at least one hydrogen atom on the haloethyl carbon atom adjacent to the sulfur atom. In contrast the hydrocarbon perchloromethyl disulfides which are known compounds, e.g. see Hawley et al. Patent 2,553,777; Birum et a1. Patent 2,717,828 and Nygaard et al. Patent 2,326,102, do not have any hydrogen atoms on the perchloromethyl group. While the perchloromethyl compounds of Hawley et al. and Birum et al. have fungicidal activity they readily decompose to compounds having inferior pesticidal activity. The compounds of the present invention are more stable than the perchloromethyl compounds. Furthermore, if there were any decomposition, it would result in the formation of hydrocarbon or haloaryl polyhalovinyl disulfides which have a nematocide, fungicide and bactericide activity of the same order as, and in some cases higher, than that of the hydrocarbon or haloaryl polyhaloethyl compounds from which they are derived.

The compounds of the present invention as indicated above can be dehydrohalogenated to give hydrocarbon (or haloaryl) polyhalovinyl disulfides. Such compounds are very useful nematocides, fungicides and bactericides as is set forth in application Serial No. 158,887, filed December 12, 1961, and entitled Asymmetric Disulfides. The prior art perchloromethylcompounds cannot be so dehydrohalogenated to obtain compounds analogous to the polyhalovinyl compounds.

The compounds of the present invention are readily distinguished from the halogenated tertiary alkyl disulfides disclosed in Eby Patent 2,560,421. While Eby considered it essential that there be two tertiary carbon atoms attached to the sulfur atoms it will be observed that the carbon atom of the polyhalo group of the present invention is a secondary carbon atom.

It has further been proposed by Kleiman in Patents 2,510,893, 2,510,894, 2,610,967 and 2,610,968 to prepare ethyl 2-chloroethyl disulfide. This compound does not have the outstanding pesticidal activity, eg nematocidal activity of the ethyl 2,2,2trichloroethyl disulfide of the present invention. Furthermore the compounds of Kleiman cannot be dehydrohalogenated to give hydrocarbon (or haloaryl) polyhalovinyl disulfides.

Examples of compounds coming within the present invention are methyl 1,2,2-trichloroethyl disulfide,

ethyl 1,2,2-trichloroethyl disulfide,

n-propyl 1,2,2-trichl0roethyl disulfide, isopropyl 1,2,2-trichloroethyl disulfide, n-butyl 1,2,2-trichloroethyl disulfide,

sec. butyl 1,2,2-trichloroethyl disulfide, isobutyl 1,2,2-trichloroethyl disulfide, tertiary butyl 1,2,2-t1'ichloroethyl disulfide, n-amyl 1,2,2-trichloroethyl disulfide,

n-hexyl 1,2,2-trichl0roethyl disulfide, cyclohexyl 1,2,2-t-richloroethyl disulfide, n-heptyl 1,2,2-trich1oroethyl disulfide, n-dodecyl 1,2,2-trichloroethyl disulfide, isoheptyl 1,2,2-trich1oroethyl disulfide, benzyl 1,2,2-trichloroethyl disulfide,

phenyl 1,2,2-trichloroethyl disulfide,

p-tolyl 1,2,2-trichloroethyl disulfide,

o-tolyl 1,2,2-trichloroethyl disulfide,

m-tolyl 1,2,2-trichloroethyl disulfide,

2',3 Xylyl 1,2,2-trichloroethyl disulfide, p-butylphenyl 1,2,2-trichloroethyl disulfide, p-dodeeylphenyl 1,2,2-trichloroethyl disulfide, p-phenylphenyl 1,2,2-trichloroethyl disulfide, alpha-naphthyl 1,2,2-trichloroethyl disulfide, beta-napthyl 1,2,2-trichloroethyl disulfide, p-chlorophenyl 1,2,2-trichloroethyl disulfide, o-chlorophenyl 1,2,2-trichloroethyl disulfide, m-chlorophenyl 1,2,2-trichloroethyl disulfide, 2-chloro-4-methylphenyl 1,2,2-trichloroethyl disulfide, 2',4'-dichlorophenyl 1,2,2-trichloroethyl disulfide, p-bromophenyl 1,2,2-trichloroethyl disulfide, methyl 1,2,2-tribromoethyl disulfide,

ethyl l,2,2-tribromoethyl disulfide,

n-butyl 1,2,2-tribromoethyl disulfide,

phenyl 1,2,2-tribromoethyl disulfide,

p-tolyl 1,2,2-tribromoethyl disulfide, p-chlorophenyl 1,2,2-tribromoethyl disulfide, ethyl 1,2-dich1oro-2-bromoethyl disulfide, methyl 1-chloro-2,2-d-ibromoethyl disulfide, allyl 1,2,2-trichloroethyl disulfide,

methyl 2,2,2-trichloroethyl disulfide,

ethyl 2,2,2-trichloroethyl disulfide,

n-propyl 2,2,2-trichloroethyl disulfide, isopropyl 2,2,2-trichloroethyl disulfide, n-butyl 2,2,2-trichloroethyl disulfide, isobutyl 2,2,2-trichloroethyl disulfide, n-arnyl 2,2,2-trichloroethyl disulfide,

n-hexyl 2,2,2-trichloroethyl disulfide, cyclohexyl 2,2,2-trichloroethyl disulfide, n-heptyl 2,2,2-trichloroethyl disulfide,

allyl 2,2,2-trichloroethyl disulfide,

benzyl 2,2,2-trichloroethyl disulfide,

phenyl 2,2,2-trichloroethyl disulfide,

p-tolyl 2,2,2-trichloroethyl disulfide,

o-tolyl 2,2,2-trichloroethyl disulfide,

m-tolyl 2,2,2-trichloroethyl disulfide,

Xylyl 2,2,2-trichloroethyl disulfide, alpha-naphthyl 2,2,2 trichloroethyl disulfide,

p-butylphenyl 2,2,2-trichloroethyl disulfide,

p-chlorophenyl 2,2,2-trichloroethyl disulfide,

p-bromophenyl 2,2,2-trichloroethyl disulfide,

o-chlorophenyl 2,2,2-trichloroethyl disulfide,

m-chlorophenyl 2,2,2-trichloroethyl disulfide,

2-chloro-4-methylphenyl 2,2,2-trichloroethyl disulfide,

ethyl 2-chloro-2,2-dibromoethyl disulfide,

methyl 2,2,2-tribromoethyl disulfide,

ethyl 2,2,2-tribromoethyl disulfide n-butyl 2,2,2-tribromoethyl disulfide,

phenyl 2,2,2-tribromoethyl disulfide,

p-tolyl 2,2,2-tribromoethyl disulfide,

p-chlorophenyl 2,2,2-tribromoethyl disulfide,

o-bromophenyl 2,2,2-tribromoethyl disulfide,

methyl 1,2,2,2-tetrachloroethyl disulfide,

ethyl l,2,2,2-tetrachloroethyl disulfide,

n-propyl 1,2,2,2-tetrachloroethyl disulfide,

isopropyl 1,2,2,2-tetrachloroethyl disulfide,

n-butyl 1,2,2,2-tetrachloroethyl disulfide,

isobutyl 1,2,2,2-tetrachloroethyl disulfide,

n-amyl 1,2,2,2-tetrachloroethyl disulfide,

n-hexyl l,2,2,2-tetrachloroethyl disulfide,

cyclohexyl l,2,2,2-tetrachloroethyl disulfide,

n-heptyl 1,2,2,2-tetrachloroethyl disulfide,

benzyl l,2,2,2-tetrachloroethyl disulfide,

phenyl l,2,2,2-tetrachloroethyl disulfide,

p-tolyl 1,2,2,2-tetrachloroethyl disulfide,

p-chlorophenyl 1,2,2,2-tetrachloroethyl disulfide,

beta-naphthyl 1,2,2,2-tetrachloroethyl disulfide,

ethyl 1,2,2,2-tetrabromoethyl disulfide,

allyl l,2,2,2-tetrachloroethyl disulfide,

phenyl 1,2,2,2-tetrabromoethyl disulfide,

ethyl 1,2,2-trichloro-2-bromoethyl disulfide,

n-butyl 1,2 dibromo 2,2 dichloroethyl disulfide and p-bromophenyl l,2,2,2-tetrabromoethyl disulfide.

For most of the uses it is preferred that R be a normal or isoalkyl group of not over 7 carbon atoms or benzyl or phenyl or lower alkyl phenyl or chloro or bromophenyl. When R is alkyl most desirably it is not over carbon atoms. The nematocidal and fungicidal activity of com pounds where R is a tertiary alkyl group is quite weak compared to the corresponding normal alkyl compounds.

While the compounds of the present invention are par ticularly noted for their nematocidal activity, in many cases they also exhibit fungicidal activity and bactericidal activity. Some of the compounds have nematocidal ac tivity at rates as low as 1 p.p.m. and were 100% effective at 3 ppm.

The compounds of the present invention are prepared by reacting the appropriate polyhaloethyl sulfenyl chlo ride or bromide with the desired aliphatic or aromatic mercaptan.

The temperature of reaction can be varied, e.g. room temperature can be employed. However, preferably the reaction is initiated at lower temperatures since the sulfenyl halides have a tendency to decompose at elevated temperatures.

The general procedure employed in Examples 1-16 (unless otherwise noted in the example) for preparing the polyhaloethyl alkyl (or aryl, or chloroaryl or benzyl) disulfide was as follows:

A known quantity of the mercaptan was dissolved in 23 parts of dry chloroform or carbon tetrachloride as a solvent and then the polyhaloethyl sulfenyl chloride was added dropwise with cooling to 48 C. The reaction proceeded rapidly and smoothly, taking about 30 minutes. The concentration of the gaseous hydrogen chloride formed during the reaction was reduced by applying a vacuum of 200-250 mm. Hg throughout the reaction period. After allowing the reaction mixture to stand at room temperature for 2 hours (or in some cases overnight), the solvent and residual gaseous hydrogen chloride were removed in vacuum. Yields of 80% to quantitative of the desired products were obtained as crude residues which in most cases were further purified by distillation in high vacuum.

Unless otherwise indicated all parts and percentages are by weight.

EXAMPLE 1 20 grams (0.1 mol) of 1,2,2trichloroethyl sulfcnyl chloride were dissolved in 25 m1. of chloroform and gaseous methyl mercaptan added at 05 C. until the solution decolorized to give a 95% yield of methyl 1,2,2-trichloroethyl disulfide as an oil, 11 1.5756, d 1.515, Cl 50.7% (theory 50.2%), S 30.2% (theory 30.3%).

EXAMPLE 2 EXAMPLE 3 The procedure of Example 2 was repeated using 9.55 grams (0.1255 mol) of isopropyl mercaptan and 25.1 grams (0.1255 mol) of 1,2,2-trichloroethyl sulfenyl chloride to obtain isopropyl 1,2,2-trichloroethyl disulfide as an oil in a yield of 21 1.5462, d 1.370, CI 45.2% (theory 44.3%), S 26.1% (theory 26.7%).

EXAMPLE 4 The procedure of Example 2 was repeated using 10.7 grams (0.1185 mol) of n-butyl mercaptan and 23.7 grams (0.1185 mol) of 1,2,2-trichloroethyl sulfcnyl chloride to obtain n-butyl 1,2,2-trichloroethyl disulfide as an oil in a yield of 11 1.5409, @1 1.328, Cl 42.2% (theory 41.8%), S 24.9% (theory 25.3%).

EXAMPLE 5 The procedure of Example 2 was repeated using 10.7 grams (0.1185 mol) of t-butyl mercaptan and 23.7 grams (0.1185 mol) of 1,2,2-trichloroethyl sulfcnyl chloride to obtain t-butyl 1,2,2-trichloroethyl disulfide as an oil in a yield of 95%, 11 1.5389, d 1.316, Cl 42.6% (theory 41.8%), S 25.1% (theory 25.3%).

EXAMPLE 6 The procedure of Example 2 was repeated using 13.4 grams (0.1018 mol) of n-heptyl mercaptan and 20.3 grams (0.1018 mol) of 1,2,2-trichloroethyl sulfenyl chloride to obtain n-heptyl 1,2,2-trichloroethyl disulfide as an oil in a yield of 90%, 12 1.5235, 07 1.227, Cl 36.7% (theory 35.9%), S 20.0% (theory 21.6%

EXAMPLE 7 The procedure of Example 2 was repeated using 16.6 grams (0.0822 mol) of n-dodecyl mercaptan and 16.4 grams (0.0822 mol) of 1,2,2-trichloroethyl sultenyl chloride to obtain n-dodecyl 1,2,2-trichloroethyl disulfide as a yellow oil in a yield of 95%, 11 1.5080, Cl 29.2% (theory 29.0%), S 16.8% (theory 17.5%).

EXAMPLE 8 The procedure of Example 2 was repeated using 8.67 grams (0.07 mol) of benzyl mercaptan and 13.94 grams (0.07 mol) of 1,2,2-trichloroethyl sulfcnyl chloride to obtain benzyl 1,2,2-trich1oroethyl disulfide in a quantitative yield as an oil, n 1.6064, 1 1.397, Cl 37.2% (theory 36.9%), S 21.4% (theory 23.3%).

EXAMPLE 9 The procedure of Example 2 was repeated using 8.06 grams (0.0734 mol) of thiophenol and 14.66 grams (0.0734 mol) of 1,2,2-trichloroethyl sulfenyl chloride to obtain phenyl 1,2,2-trichloroethyl disulfide as an oil in quantitative yield, n 11.619 7 d 1.443, Cl 38.4% .(theory 38.8%), S 23.0% (theory 23.4%).

EXAMPLE 10 The procedure of Example 2 was repeated using 12.95 grams (0.1045 mol) of p-toluenethiol and 20.9 grams (0.1045 mol) of 1,2,2-trichloroethyl sulfenyl chloride to obtain p-tolyl 1,2,2-trichloroethyl disulfide as a yellow oil in a yield of 92%,11 1.6088, (1 1.399, Cl 37.6% (theory 36.9%), S 21.5% (theoryj22.3%

EXAMPLE 11 The procedure of Example ZWas repeated using 14.05 grams (0.0975 mol) of p-chlorothiophenol and 19.5

grams (0.0975 mol) of -1,2,2-t-richloroethylsulfenyl-chloride to obtain p-chlorophenyl 1,2,2-trichloroethyl disulfide ,as a yellow oil in a yield of 95%, 11 5 1.6265, 81 1.525, Cl 46.1% (theory 46.0%), S 20.9% (theory 20.8%

EXAMPLE 12 The procedure of Example 1 was repeated using gaseous methyl mercaptan and 10 grams (0.05 mol) of 2,2,2- t-richloroethyl-sulfenyl chloride to obtain methyl 2,2,2- trichloroethyl disulfide as a colorless oil B.P. 5657 C. at 0.07 mm. Hg, 11 1.5614, d 1.481, Cl 50.0% (theory 50.2%), S 30.8% (theory 30.3%).

EXAMPLE 13 The procedure of Example 2 was repeated using 8.3 grams (0.134 mol) of ethyl mercaptan and 26.7 grams (0.134 mol) of 2,2,2-trichloroethyl sulfenyl chloride to obtain ethyl 2,2,2-trichloroethyl disulfide as a colorless oil in a yield of 98%, 11 1.5485, 41. 1.404, Cl. 47.4% (theory 47.0%), S 27.7% (theory 28.4%).

EXAMPLE 14 The procedure of Example 2 was repeated using 13.5 grams (0.1018 mol) of n-heptyl mercaptan and 20.3 grams (0.1018 mol) of 2,2,2-trichloroethyl sulfenyl chloride to obtain n-heptyl 2,2,2-trichloroethyl disulfide as an oil in a quantitative yield, 11 1.5145, Cl 34.8% (theory 35.9%), S 22.3% (theory 21.6%).

EXAMPLE 15 The procedure of Example 2 was repeated using 12.95 grams (0.1045 mol) of p4toluenethiol and 20.9 grams (0.1045 mol) of 2,2,2-trichloroethyl sulfenyl chloride to obtain p-tolyl 2,2,2-trichloroethyl disulfide as .a yellow oil in a yield of 93.5%, n 1.6030, d 1.227, Cl 37.1% (theory 36.9%), S 21.4% (theory 22.3%

EXAMPLE 16 The procedure of Example 2 was repeated using 14.5 grams (0.0972 mol) of p-chlorothiophenol and 19.4 grams (0.0972 mol) of 2,2,2-trich1oroethyl sulfenyl chloride to obtain p-chlorophenyl 2,2,2-trichloroethyl disulfide as a yellow oil in quantitative yield, 11 1.6200, 21 1.497, Cl 45.6% (theory 46.0%), S 20.7% (theory 20.8%).

As previously stated the compounds of the present invention can be employed to prepare polyhalovinyl alkyl disulfides having one less halogen atom by dehydrohalogenation as shown in Examples 17-21. The polyhalovinyl alkyl disulfides are useful as nematocides, fungicides and bactericides as is more fully set forth in the aforementioned application.

EXAMPLE 17 To 10 grams (0.0475 mol) of methyl 1,2,2-trichloroethyl disulfide dissolved in ml. of heptane were added dropwise 4.85 grams (0.0475 mol) of triethyl amine at 35-40 C. The mixture was then allowed to stand overnight at room temperature. The triethyl amine hydrochloride formed was removed by washing with water. The unreacted triethyl amine was removed by washing the organic layer first with dilute hydrochloric acid followed by dilute aqueous sodium bicarbonate and 'water'. The heptane solution was then dried over anhydrous magnesium sulfate and the solvent removed in a high vacuum. The product was methyl 1,2-dichlorovinyl disulfide, an oil obtained in a yield of 60% EXAMPLE 18 The procedure of Example 17 was repeated using 15 grams (0.0591 mol) of n-butyl 1,2,2-trichloroethyl disulfide with 6.05 grams (0.0591 mol) of triethyl amine to give an 83% yield of n-butyl 1,2-dichlorovinyl disulfide as an oil.

EXAMPLE 19 The procedure of Example 17 was repeated using 18.3 grams (0.05 mol) of n-dodecyl 1,2,2-trichloroethyl disulfide with 5.06 grams (0.05 mol) of triethyl amine to give an 88.5% yield of n-dodecyl 1,2-dichloroviny1 disulfide as a dark oil.

EXAMPLE 20 The procedure of Example 17 was repeated using 14.4 grams (0.05 mol) of p-tolyl 1,2,2-trichloroethyl disulfide with 5.06 grams (0.05 mol) of triethyl amine to give a 92% yield of p-tolyl 1,2-dichlorovinyl disulfide as a dark oil.

EXAMPLE 21 The procedure of Example 17 was repeated using 15.4 grams (0.05 mol) of p-chlorophenyl 1,2,2-trichloroethyl disulfide with 5.06 grams (0.05 mol) of triethyl amine to give an 89% yield of p-chlorophenyl 1,2-dichlorovinyl disulfide as a dark oil.

The compounds of the present invention can be used alone as nematocides, fungicides and bactericides but it has been found desirable to apply them to the pest, e.g. to the soil habitat of nematodes, together with inert solids to form dusts, or more preferably suspended in a suitable liquid diluent, preferably water. There can also be added surface active agents and inert solids in such liquid formulations. Desirably, 0.051% by weight of surface active agent is employed. The active ingredient can be from 0.01 to 95% by weight of the entire composition in such cases.

In place of water there can be employed organic solvents as carriers, e.g. hydrocarbons such as benzene, toluene, xylene, kerosene, diesel oil, fuel oil, and petroleum naphtha, ketones such as acetone, methyl ethyl ketone and cyclohexanone, chlorinated hydrocarbons such as carbon tetrachloride, chloroform, trichloroethylene and perchloroethylene, esters such as ethyl acetate, amyl acetate and butyl acetate, ethers, e.g. ethylene glycol monomethyl ether and diethylene glycol monomethyl ether, alcohols, e.g. ethanol, isopropanol and amyl alcohol, etc.

The novel pesticides can also be applied as aerosols, e.g. by dispersing them in air by means of a compressed gas such as dichlorodifluoromethane or trichlorofiuoromethane and other Freons for example.

The pesticides of the present invention can also be applied with inert nematocidal, fungicidal, bactericidal or insecticidal adjuvants or carriers such as talc, pyrophyllite, synthetic fine silica, Attaclay, kieselguhr, chalk, diatornaceous earth, lime, calcium carbonate, bentonite, fullers earth, cottonseed hulls, wheat flour, soyabean flour, pumice, tripoli, wood flour, walnut shell flour, redwood flour and lignin. 7

It is frequently desirable to incorporate a surface active agent in the pesticidal compositions of this invention. Such surface active agents, i.e. wetting agent, are advantageously employed in both the solid and liquid compositions. The surface active agent can be anionic, cationic or nonionic in character.

Typical classes of surface active agents include alkyl sulfonate salts, alkylaryl sulfonate salts, alkyl sulfate salts, alkylamide sulfonate salts, alkylaryl polyether alcohols, fatty acid esters of polyhydric alcohols and the alkylene oxide addition products of such esters, and addition products of long chain mercaptans and alkylene oxides. Typical examples of such surface active agents include the sodium alkyl benzene sulfonates having 14 to 18 carbon atoms in the alkyl group, alkylphenolethylene oxide condensation products, e.g. p-isooctylphenol condensed with ethylene oxide units, soaps, e.g. sodium stearate and potassium oleate, sodium salt of propylnaphthalene sulfonic acid, (di-Z-ethyl hexyl) ester of sodium sulfosuccinic acid, sodium lauryl sulfate, sodium salt of the sulfonated monoglyceride of cocoanut fatty acids, sorbitan sesquioleate, lauryl trimethyl ammonium chloride, octadecyl trimethyl ammonium chloride, polyethylene glycol lauryl ether, polyethylene esters of fatty acids and rosin acids, e.g. Ethofat 7 and 13, sodium N-methyl-N-oleyltaurate, Turkey red oil, sodium dibutylnaphthalene sulfonate, sodium lignin sulfonate (Marasperse N), polyethylene glycol stearate, sodium dodecylbenzene sulfonate, tertiary dodecyl polyethylene glycol thioether (Nonionic 218), long chain ethylene oxide propylene oxide condensation products, e.g. Pluronic 61, sorbitan monolaurate, polyethylene glycol ester of tall oil acids, sodium octylphenoxyethoxyethyl sulfate, tris (polyoxyethylene) sorbitan monostearate (Tween 60), sodium dihexyl sulfosuccinate.

The solid and liquid formulations can be prepared by any of the conventional methods. Thus the active ingredient can be mixed with the solid carrier in finely divided form in amounts small enough to preserve the freeflowing property of the final dust composition.

In the following examples or tables illustrating nematocidal activity the disulfides were formulated as wettable powders consisting of 50% of the disulfide, 46% Hi-Sil 233 (ultra fine silica), 2% Marasperse N (sodium lignin sulfonate) and 2% Pluronic L61 (polyethylene oxidepropylene oxide molecular weight about 1000). This wettable powder is hereinafter designated as Formulation A.

These 50% by weight disulfide containing wettable powders were diluted with water to such an extent as to obtain final concentrations of the disulfides of 200, 100, 50, 25, 12.5, 6, 3 and 1 p.p.m. during the actual tests.

The saprophytic nematode tests were carried out in Water as the medium with Panagrellus and Rhabditis spp. at room temperature. The results were recorded as percent kill after a 4 days incubation period. The blank mortality was a 5-10% kill.

The compounds employed in the tests as nematocides, fungicides and bactericides had the formula R SSR where R is the radical indicated in the tables and R is designated in the tables as 1,2,2-trichloro or 2,2,2-trichloro depending upon which trichloroethyl group was present as R Table 1 p-To1yl p-Chlorophenyl Those compounds which showed up best in the tests recorded in Table 1 were further tested against the saprophytic nematodes at reduced amounts as shown in Table 2.

Eth

8 Table 2 Percent Kill of Saprophytic Nematodes R R5 Rates p.p.m.

In commercial practice the compositions containing the nematocides of the present invention are applied to the soil infested with nematodes.

The compounds were also tested as bactericides as indicated in Table 3. The compounds were incorporated in Formulation A and this mixture added to an agar culture of the bacteria. In Table 3 a indicates bactericidal activity at the concentration employed and n indicates no activity. The concentrations are in p.p.m.

Table 3 Erwinia Paeudomo- Xanthocaroluvora nae coronamonas vesiaciens calorie R R4 f Methyl 1, 2,2-trieh1oro a n n n n 11 do a n n n n n d n n a n a n d a n a n a n do. a n n n n 11 do n n a n n n do n n a n a n 2, 2, 2-tr1chlor0 a n a n a 11 d0 a n n n 11 11 do a a a a a n The compounds were also tested as fungicides in plate fungicide tests as indicated in Table 4. The compounds were made up into Formulation A and then added to agar cultures of the fungi. In the table 10 indicates 100% effectiveness and 0 indicates no effectiveness. In Table 4 P stands for Pythium spp., F for Fusarium, R for Rhizoctonia, H for Helminthosporium and S for Stemphylliam sarcinaeformae. The concentrations are expressed as p.p.m.

Table 4 P F R H S R1 6 4 0 O 0 7 3 4 O 10 2 0 0 0 0 4 0 O 0 1O 8 1O 10 0 0 8 3 8 5 10 10 10 10 6 0 0 O 0 O 10 5 10 4 O 0 O O 0 0 10 10 0 0 O 0 8 4 3 U 0 O 10 4 4 0 0 0 0 0 0 0 4 O 0 O 2 0 0 O 5 1 0 0 2 0 O O 2 0 10 0 1O 4 O 0 4 0 0 0 1O 3 10 1O 0 O 4 O 5 1 10 10 1O 3 4 U G 4 0 0 0 0 n-HeptyL 4 0 0 U 3 0 0 O 0 0 We claim:

1. n-Alkyl 2,2,2-trichloroethyl disulfides having 1 to 5 carbon atoms in the alkyl group.

2. Phenyl trichloroethyl disulfides.

3. Lower alkylphenyl trichloroethyl disulfides.

4. Monochlorophenyl trichloroethyl disulfides.

5. Benzyl trichloroethyl disulfides.

6. Isoalkyl trichloroethyl disulfides having 3 to 7 carbon atoms in the isoalkyl group.

7. Methyl-1,2,2-trichloroethyl disulfide.

8. Isopropyl-1,2,2-trichloroethyl disulfide.

9. n-Butyl-1,2,2-trichloroethyl disulfide.

10. A process of preparing a compound having the formula Where X is a halogen atom having an atomic weight between and 80.

11. A process according to claim 10 wherein all halogen atoms are chlorine atoms.

References Cited in the file of this patent UNITED STATES PATENTS 2,469,404 Patrick May 110, 1949 2,553,772 Kittleson et al. May 22, 1951 2,796,437 Park June 8, 1957 2,917,429 Scott Dec. 15, 1959 FOREIGN PATENTS 1,171,688 France Jan. 29, 1959 OTHER REFERENCES Reid: Organic Chemistry of Bivalent Sulfur, vol. 1, p. 274, Chemical Publishing Co., Inc., 212 Fifth Ave., New York, NY.

Knunyants et al.: Isvest Akad Nauk SSSR Otdel Khim Nauk, 1952, 261-267. Cited in Chemical Abstracts 47, 3221d (1953). 

1. N-ALKYL 2,2,2-TRICHLOROETHYL DISULFIDES HAVING 1 TO 5 CARBON ATOMS IN THE ALKYL GROUP.
 10. A PROCESS OF PREPARING A COMPOUND HAVING THE FORMULA 